Relative humidity sensor with compensation for changes in pressure and gas composition

A system for sensing the relative humidity of a fuel cell comprising:

• a humidity sensor that senses the relative humidity of a gas stream supplied to an electrode of said fuel cell and that generates a relative humidity signal;
• a first sensor that senses at least one of pressure and temperature of said gas stream and generates at least one of a temperature signal and a pressure signal;
• and
• a compensator that is connected to said humidity sensor and said first sensor and that generates a compensated relative humidity signal based on said relative humidity signal and said at least one of said temperature signal and said pressure signal;
• and
• a gas composition sensor for sensing a concentration of a first gas in said gas stream and for generating a first gas concentration signal.

A system for sensing the relative humidity of a fuel cell, comprising:

• a humidity sensor that senses the relative humidity of a gas stream and generates a humidity signal;
• a gas composition sensor for sensing a concentration of a first gas in said gas stream and for generating a first gas composition signal;
• and
• a compensator that is connected to said humidity sensor and said temperature sensor and that generates a compensated relative humidity signal based on said relative humidity signal and said first gas composition signal.

A system for sensing the relative humidity of a fuel cell, comprising:

• a humidity sensor that senses the relative humidity of a hydrogen-containing gas stream and generates a relative humidity signal;
• a first sensor that senses at least one of pressure and temperature of said gas stream and generates at least one of a temperature signal and a pressure signal;
• and
• a compensator that is connected to said humidity sensor and said first sensor and that generates a compensated relative humidity signal based on said relative humidity signal and said at least one of said temperature signal and said pressure signal.